Abstract
This paper describes the characteristics of wind forces acting on a rotating propeller-type wind turbine generator system with three blades. The wind forces on the blades, the tower and the rotor (components of the wind turbine generator system), and on the wind turbine tower assembly were investigated from wind tunnel tests. The following results were obtained. First, the thrust acting on the wind turbine rotor increased as the tip speed ratio increased or the pitch angle decreased. Second, if an appropriate pitch angle was chosen, the mean overturning moments in the along-wind direction on the wind turbine tower corresponded to the full-scale values. Furthermore, relations between the chosen pitch angle and wind velocity were similar to those of the actual wind turbine. Lastly, in the along-wind direction, the mean overturning moments were not influenced by the turbulence intensity and scale, but the fluctuations of overturning moment were greatly influenced by the turbulence intensity and scale.
